Hisamatsu T¹, Ohno A¹, Chiba T².

Dig Endosc. 2017 Nov 27. doi: 10.1111/den.12992. [Epub ahead of print]

Ulcerative colitis (UC) associated colorectal cancer (CRC) is an important issue in long-term management of patients with UC. Lesions with chronic inflammatory mucosa as background may often be difficult to identify even by endoscopic observation. Traditionally, a random biopsy strategy was recommended, but problems with patient compliance, increased burden on endoscopic staff and pathologists, were left. This article is protected by copyright. All rights reserved.

^{1 Third Department of Internal Medicine, Kyorin University School of Medicine.
2 Department of Pathology, Kyorin University School of Medicine.}

Wu CH^1,2, Chen TH^1,2,3, Hsu CM^1,2, Su MY^1,2, Chiu CT^1,2, Wu RC⁴, Lai CC⁵.

Ther Clin Risk Manag. 2017 Oct 3;13:1317-1321.

Introduction: Linked-color imaging (LCI) is a recently developed system used in endoscopy. It creates clear and bright endoscopic images using short-wavelength, narrow-band laser light combined with white laser light. The illuminating light and signal processing emphasize slight color differences in abnormal regions that approximate the normal color of the mucosa. As a result, regions initially appearing red become a deeper shade of red, while regions originally appearing white become brighter, yet with natural tones. This process facilitates recognition of slight differences in the color of the mucosa and clarifies the boundaries of the mucosal pit.

Aim: To determine whether LCI of the colon can improve the correlation between endoscopic findings and pathological diagnosis.

Methods: Consecutive patients who underwent colonoscopy requiring polypectomy or removal by biopsy forceps if possible were recruited. Probable polyp histology was assessed by two endoscopists using the Narrow-band imaging International Colorectal Endoscopic (NICE) classification and LCI data. All detected polyps were sent to the pathology department for pathological diagnosis by two pathologists.

Results: In total, 94 polyps were found in 43 patients. The sensitivity, specificity, positive predictive value, and negative predictive value for neoplastic lesion prediction (NICE type2/3) were 96.5%, 83.8%, 90.2%, and 93.9%, respectively.

Conclusion: LCI combined with the NICE classification system is a powerful tool for predicting probable histology of colon polyps.

^{1 Department of Gastroenterology and Hepatology, Linkou Medical Center, Chang Gung Memorial Hospital, Taoyuan.
2 Chang Gung University, College of Medicine, Taoyuan.
3 Graduate Institute of Clinical Medical Sciences, Chang Gung University, Taoyuan.
4 Department of Pathology, Linkou Medical Center, Chang Gung Memorial Hospital, Taoyuan.
5 Department of Colon and Rectal Surgery, Linkou Medical Center, Chang Gung Memorial Hospital, Taoyuan, Taiwan.}

Goda Y¹, Mori H¹, Kobara H¹, Nishiyama N¹, Kobayashi N¹, Yachida T¹, Masaki T¹.

Endoscopy. 2017 Oct 17. doi: 10.1055/s-0043-119984. [Epub ahead of print]

Linked color imaging (LCI; Fujifilm Co., Tokyo, Japan) is a newly developed image- enhanced technique that has shown high diagnostic performance in the field of gastrointestinal endoscopy. LCI enhances color separation of the mucosal layer, making red regions redder and white regions whiter. This contributes to the detection of gastric cancer [1], ulcerative colitis [2], colorectal polyps [3, 4], and other lesions. Although the diagnostic productivity is steadfast, the treatment benefit of LCI remains unclear or limited [5]. We herein introduce an advantage of LCI with respect to increasing the safety of endoscopic mucosal resection (EMR), illustrating the efficacy of LCI in the treatment field.

Compared with white-light imaging, narrow- band imaging, and bright-light imaging, the view of the blood vessels in the superficial layer is much more conspicuous when obtained by LCI. When performing EMR, local injection is the first crucial step and the basis of later procedures such as polyp removal by snaring. However, injury to the superficial vessels invisible with white light sometimes induces hematoma formation, making subsequent snaring difficult (▶Fig. 1 a). LCI can more precisely reveal the running of the superficial vessels around a colorectal polyp than can white light imaging (▶Fig. 1 b) and bright-light imaging (▶Fig. 1 c). LCI enhances the reddish, glaring characteristics of the vessels, pinpointing safe sites for needling (▶Fig. 1 d). Consequently, the clinician can avoid needling blood vessels near the polyp (▶Fig. 1 e) and prevent unnecessary bleeding and hematoma formation (▶Fig. 1 f), leading to secure completion of EMR.

White-light imaging, bright-light imaging, and LCI for EMR local injections are compared in ▶Video 1. Only LCI shows the reddish network pattern of the superficial blood vessels. This leads to sufficient swelling of the submucosal layer and appropriate removal of colorectal polyps.

Fig. 1 Endoscopic images illustrating the advantages of linked color imaging (LCI) during endoscopic mucosal resection. a Improper injection can induce hematoma formation. b Superficial vessels around a colorectal polyp are invisible with white-light imaging. c Superficial vessels are also unclear with bright-light imaging. d LCI shows the orientation of vessels around the polyp. e The injection needle pinpoints a site lacking vessels. f Unnecessary hematoma formation and bleeding can be avoided during mucosal injection.

Video 1 White-light imaging only ambiguously shows the blood vessel routes, whereas linked color imaging (LCI) indicates the vessels clearly as a vivid reddish color. From injection to snaring, LCI allows the clinician to avoid unnecessary bleeding.

¹Department of Gastroenterology and Neurology, Faculty of Medicine, Kagawa University, Kagawa, Japan.

Kono Y¹, Kawahara Y², Okada H¹.

Clin Gastroenterol Hepatol. 2017 Sep 1. pii: S1542-3565(17)31045-5.

Chromoendoscopy (CE) and image-enhanced endoscopy are useful for accurately diagnosing gastric neoplasms. However, unclear lesions, such as those with a flat morphology or normochromic color, sometimes can be missed. We herein present a case in which CE was performed with the combined use of an acetic acid indigo carmine mixture (AIM) and linked-color imaging (LCI), and this method was effective for detecting early gastric cancer. A Japanese man in his 70s underwent esophagogastroduodenoscopy for screening purposes. It was difficult to identify any lesions by white-light imaging (Figure A).

However, when performing image-enhanced endoscopy with LCI, a shallow depressed lesion was identified in the prepyloric area and this modality made it easier to detect the lesion, but the visibility was insufficient to distinguish clearly between the lesion and the surrounding area (Figure B). CE using an AIM with LCI enhanced not only the surface color, but also the demarcation line of the lesion (Figure C). A histologic examination of a biopsy specimen showed differentiated-type adenocarcinoma, and endoscopic submucosal dissection thereafter was performed.

The pathologic diagnosis of the resected specimen showed well-differentiated adenocarcinoma of the stomach (Figure D). Performing CE using an AIM and LCI is useful for detecting gastric neoplasms.

Uchiyama K¹, Takagi T¹, etc.

J Crohns Colitis. 2017 Feb 22 Impact factor 6.585

Background and Aims: Mucosal healing and control of intestinal mucosal inflammation are important treatment goals for maintaining clinical remission in ulcerative colitis (UC) patients. Here, we investigated the efficacy of LCI, a novel endoscopic enhancement system, to diagnose mucosal inflammation in UC patients.

Methods: All examinations were carried out with a LASEREO endoscopic system (FUJIFILM Co., Tokyo, Japan). Fifty-two patients with UC were enrolled, and 193 areas assessed by LCI were examined. LCI patterns were classified as A, no redness; B, redness with visible vessels; and C, redness without visible vessels. ROI were set at biopsy sites, and red colour in the ROI was calculated as Commission internationale de l’éclairage (CIE) color space and digitized (LCI-index). Biopsy specimens were taken at each ROI and evaluated with Matts histopathological grade. Thirty months was defined as the time interval between endoscopic diagnosis and relapse of UC.

Results: Inter-observer agreement for LCI classification was excellent between an expert and non-experts. Among areas with a Mayo endoscopic subscore of 0, 41.8% and 4.6% were classified as LCI-B and C respectively. Among areas with Mayo endoscopic subscore of 1, 60.5% and 34.6% were classified as LCI-C, and B respectively. LCI-index strongly correlated with histopathological Matts score. Non-relapse rates significantly correlated with LCI classification (p=0.0055), but not with Mayo endoscopic subscore (p=0.0632).

Conclusions:Endoscopic LCI classification and LCI index can subdivide samples with the same Mayo endoscopic subscore. LCI may be a novel approach to evaluate colonic mucosal inflammation and predict outcome in UC patients.